With just 3 years left until the 2020 Olympics, Japan is likely desperate to reassure the world's athletes that all is well, but an admission from TEPCO - the Fukushima nuclear plant operator - that they discovered a hole at least one square meter in size beneath the reactor's pressure vessel, and lethal record-high radiation levels have been detected, will not likely reassure anyone.

Radiation levels of up to 530 Sieverts per hour were detected inside an inactive Reactor 2 at the Fukushima Daiichi nuclear complex damaged during the 2011 earthquake and tsunami catastrophe, Japanese media reported on Thursday citing the plant operator, Tokyo Electric Power Company (TEPCO). A dose of about 8 Sieverts is considered incurable and fatal.

As RT reports, a hole of no less than one square meter in size has also been discovered beneath the reactor's pressure vessel, TEPCO said. According to researchers, the apparent opening in the metal grating of one of three reactors that had melted down in 2011, is believed to be have been caused by melted nuclear fuel that fell through the vessel.

The iron scaffolding has a melting point of 1500 degrees, TEPCO said, explaining that there is a possibility the fuel debris has fallen onto it and burnt the hole. Such fuel debris have been discovered on equipment at the bottom of the pressure vessel just above the hole, it added.

The latest findings were released after a recent camera probe inside the reactor, TEPCO said. Using a remote-controlled camera fitted on a long pipe, scientists managed to get images of hard-to-reach places where residual nuclear material remained. The substance there is so toxic that even specially-made robots designed to probe the underwater depths beneath the power plant have previously crumbled and shut down.

However, TEPCO still plans to launch further more detailed assessments at the damaged nuclear facility with the help of self-propelled robots.

TEPCO confirmed a black lump in the space beneath the pressure vessel. There is a possibility of nuclear fuel melting down (fuel debris). If it is fuel debris, it will be the first time that fuel melted down will be taken after the Fukushima Daiichi nuclear accident.